Research

A bigger finance target alone may not work. The authors suggest a separate target for grants, which could raise accountability, trust and transparency.“Post-2025 climate finance target: how much more and how much better?.” Identifies five priority elements for the post-2025 target (relation to Article 2.1(c), adaptation-mitigation balance, financial instruments, mobilising private finance, 'new and additional' finance) and suggests setting a sub-target for grants.

The authors argue that science can now link economic losses from extreme heat to the emissions of individual fossil fuel companies.“Carbon majors and the scientific case for climate liability.” End-to-end attribution links fossil fuel producers' scope 1 and 3 emissions to specific heat-related economic losses. For Chevron, emissions very likely caused between US $791 billion and $3.6 trillion in heat-related losses over the period 1991-2020.

A review of 1,682 articles found that the overall extent of adaptation to climate change is low, and most efforts are local and small-step rather than transformative. Evidence that these efforts are reducing risks remains limited.“A systematic global stocktake of evidence on human adaptation to climate change.” A systematic global stocktake screened 48,316 documents and coded 1,682 empirical articles: adaptation is low in extent, largely local and incremental rather than transformative, and evidence that responses reduce observed or projected risk remains limited.

About one in three heat deaths in the places studied can be blamed on human-caused warming.“The burden of heat-related mortality attributable to recent human-induced climate change.” 732 locations, 43 countries, 1991–2018: 37% of warm-season heat deaths attributable.

Money and weak institutions are the most common reasons adaptation stalls.“Global evidence of constraints and limits to human adaptation.” Financial and governance constraints dominate; evidence on hard limits remains thin.

Researchers looked back at 1500 climate policies across 41 countries and found 63 that led to large cuts in emissions. They say price-based policies play an important role in well-designed policy mixes.“Climate policies that achieved major emission reductions: Global evidence from two decades.” Ex post evaluation of 1500 policies (1998 to 2022, 41 countries) using a machine learning-based extension of difference-in-differences identified 63 successful interventions with total emission reductions between 0.6 billion and 1.8 billion metric tonnes CO2.

Human-caused warming is estimated at 1.36 °C in 2024, and it is rising at a rate that is unprecedented in the instrumental record.“Indicators of Global Climate Change 2024.” Human-induced warming is increasing at 0.27 [0.2-0.4] °C per decade over 2015-2024, driven by greenhouse gas emissions at an all-time high of 53.6±5.2 Gt CO2e yr-1 (2014-2023) and reduced aerosol cooling; the 2024 observed best estimate is 1.52 °C versus 1.36 °C human-caused.

Temporarily passing a warming limit and then cooling back down is not something we can count on, because strong feedbacks in the Earth system could undercut the cooling. Only rapid near-term emission cuts are effective in reducing climate risks.“Overconfidence in climate overshoot.” Declining global temperatures after overshoot can limit long-term risks (including sea-level rise and cryosphere changes) compared with mere stabilization, but reversal could be undercut by strong Earth-system feedbacks; the authors identify a geophysical need for a preventive carbon dioxide removal capacity of several hundred gigatonnes, which technical, economic and sustainability considerations may limit.

Meeting the well-below 2°C goal would increase energy jobs worldwide, from 18 million today to 26 million by 2050, compared with 21 million under current policies. Fossil fuel extraction jobs would decline, but gains in solar and wind jobs would make up for the losses.“Meeting well-below 2°C target would increase energy sector jobs globally.” Combining job intensities across 11 energy technologies and five job categories in 50 countries with an integrated assessment model under three shared socioeconomic pathways, direct energy jobs reach 26 million by 2050 under a WB2C scenario versus 21 million under current policy; solar and wind gains, particularly in manufacturing (7.7 million in 2050), compensate for fossil extraction losses.

For an even chance of 1.5°C, nearly 60% of oil and gas and 90% of coal must stay in the ground by 2050.“Unextractable fossil fuels in a 1.5 °C world.” By 2050, nearly 60 per cent of oil and fossil methane gas and 90 per cent of coal must remain unextracted for a 50 per cent probability of limiting warming to 1.5 °C, using a global energy systems model.

Existing and under-construction oil and gas fields and coal mines would commit 936 Gt CO2. Staying within a 1.5 °C carbon budget (50% probability) means leaving almost 40% of developed reserves of fossil fuels unextracted.“Existing fossil fuel extraction would warm the world beyond 1.5 °C.” Central estimate of committed CO2 emissions from fossil fuel-producing infrastructure (existing and under-construction oil and gas fields and coal mines) is 936 Gt CO2: 47% coal, 35% oil, 18% gas. Developed reserves substantially exceed the 1.5 °C carbon budget (50% probability), implying almost 40% must be left unextracted; robust to a Monte Carlo analysis.

The authors argue that a social-moral norm against new fossil fuel projects has strong potential to help achieve global climate goals.“No new fossil fuel projects: The norm we need.” The abstract states only that a social-moral norm against new fossil fuel projects has strong potential to contribute to achieving global climate goals.

Compared with continuing with a fossil fuel-based system, a rapid green energy transition will likely save many trillions of dollars, even before counting climate damages or other benefits of climate policy.“Empirically grounded technology forecasts and the energy transition.” Probabilistic cost forecasts for solar, wind, batteries and electrolyzers, using methods statistically validated by backtesting on more than 50 technologies, indicate that a rapid green energy transition will likely yield net savings of many trillions of dollars.

Solar power may already have passed a point of no return, after which it gradually comes to dominate global electricity markets without any further climate policies. Open questions remain over grid stability, finance in underdeveloped economies, supply chains and political resistance.“The momentum of the solar energy transition.” Data-driven conditional technology and economic forecasting suggests a global irreversible solar tipping point may have passed, with solar gradually dominating electricity markets without further climate policies; uncertainties include grid stability, finance, supply chain capacity and political resistance, and policies resolving these barriers may be more effective than price instruments.

Further progress in solar and wind technology together with carbon pricing could make electricity cheaper than carbon-based fuels. In a 1.5 °C scenario with limited bioenergy and carbon dioxide removal, electricity could supply 66% of final energy by mid-century, three times current levels.“Impact of declining renewable energy costs on electrification in low-emission scenarios.” Further solar and wind progress plus carbon pricing could make electricity cheaper than carbon-based fuels; in a 1.5 °C scenario with limited bioenergy and carbon dioxide removal, electricity could account for 66% of final energy by mid-century, three times current levels and higher than previous IPCC scenarios.